In an effort to reduce the likelihood of boating accidents after dark, government legislation in most countries stipulates mandatory use of navigational lights on boats. The standard configuration of lights comprises a single light mounted at the bow of a boat having a green lens on the starboard side and a red lens on the port side, and a single white light located at the stern of the boat.
In spite of the mandatory use of such navigational lights, it has been found that night time accidents between recreational boating vehicles is still frequent. One possible cause for the large number of collisions between boats operating at night is the almost complete inability of the boat operator to detect depth-of-field and the consequent inability to ascertain distance from and orientation of an oncoming boat. For example, instances are known in which boat operators have mistaken the navigational lights of another boat as being lights located on shore, and have collided with the other boat as a result. In such instances, the boat operators have experienced difficulties recognizing other marine traffic when relying only on the relative light and darkness provided by pin point navigational lights (i.e. essentially a two-dimensional frame of reference).
Also, both the bow and stern lights of present navigation lighting systems are known to generate glare which affects the night vision of the boat operator, both through the boat windshield and above it. In this regard, the stern light is the greatest offender since glare from the stern light is projected in all directions. Furthermore, the laws require that the stern light be raised on a pedestal which consequently increases the glare. If glare from the bow or stern lights is excessive, a boat operator's night vision may temporarily be lost which can result in an accident. In an effort to overcome the problem of glare using prior art navigation lights, operators have been known to tape the front half of the stern light in order to prevent forward shining glare from the stern light. However, taping of the front half of the stern light effectively renders the stern light invisible to other boats approaching from the bow. The stern light is therefore no longer easily visible which contributes to further confusion of other operators as to the direction of travel of the boat.
Prior art systems are known for enhancing the visibility of marine and land vehicles at night. For example, U.S. Pat. No. 4,947,293 (Johnson et al) discloses a perimeter clearing lighting system for use with tractor-trailer trucks. U.S. Pat. No. 3,723,722 (Van Inderstine et al) discloses a rotary wing mounted lighting system for helicopters. U.S. Pat. No. 4,613,927 (Brandt) discloses an elevated signal indicator for automobiles. U.S. Pat. No. 4,901,209 (Nitz) discloses an illuminated frame for bicycles. U.S. Pat. No. 4,740,870 (Moore et al) discloses a distributed lighting system for boats. U.S. Pat. No. 2,704,321 (Orlansky) discloses an illuminating system for the trailing edges of aircraft.
Various ones of the known prior art systems teach the use of distributed light in conjunction with standardized colouring for navigation. However, none of the above-discussed references provide a complete solution to the problem of providing depth of field to a boat operator during night time operation.